Railway signaling



4 Sheets-Sheet 1 Paul P. SI.

P. P. STOKER RAILWAY SIGNALING Original Filed May 19, 1932 Q 1. wwmw N WM N HN D July- 30, 1935.

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i t/ls ATTORNEY July 30, 1935. P. "P. ST OKER RAILWAY SIGNALING 4 Sheets-Sheet 2 Original Filed May 19, 1932 NQN INVENTOR PaalRSzoken v ,H19'ATT0RNEY' n bS W QQ M BEQQ H July 30, 1935. P. P. STOKER RAILWAY SIGNALING ori inal Filed May 19, 1952 4 Sheets-Sheet 5 mi? v INVENTOR Paul P. Szolzar'. '7 QQW HIS ATTORNEY .Fuly 30, 1935. P. P. STOKER RAILWAY SIGNALING 4 Sheets-Sheet 4 @NN mxwq Original Filed May 19, 1952 JJILJJIILII $3 n u lrll I. ERR? n j. u T. .u m n Ti.|||| i k5 EILEN H LE I T R: wsq afi QB. L NEW w SQ Film A Y. 0 m WWW. a MWUH Patented July 30, 1935 UNITED STATES RAILWAY SIGNALING Paul P. Stoker, Wilkinsburg, Pa., assignor to The Union Switch & Signal Company, Swissvale, Pa., a corporation of Pennsylvania Application May 19, 1932, Serial No. 612,234

Renewed November 23, 1934 18 Claims.

My invention relates to railway signaling, and particularly to signaling apparatus for governing traflic in both directions over a stretch of railway.

One feature of my invention is the provision, in signaling of the type here involved, of novel and improved means controlled in part from a remote despatchers ofiice or tower for routing traffic over a track in either direction in a manner permitting several trains to follow each other through the stretch of track, while preventing two trains moving in opposite directions from occupying the stretch at the same time. In reverse signaling systems heretofore proposed, only one train is allowed in the protected territory at a time, or if they permit following moves, they require the remote controlled trafiic governing means to remain as established for the first train until that train has completely vacated the terri- 2'0" tory. That is to say, if the first train into the protected territory moves along the main track, the remote controlled means cannot be operated from its established position to permit a change in the position of a switch leading from a sidetrack to allow a second and following train to proceed from the sidetrack into the main track until the first train has entirely cleared the protected territory. Such limitations, while providing protection, greatly hamper the flexibility of traflic movements especially where switches and signals are to be governed by centralized traffic control systems such as are in use at the present time. Accordingly, a further feature of my invention is the provision of apparatus that permits operation of the remote controlled means after a train has entered the protected territory without affecting the directional selection that has previously been made. A still further feature of my invention lies in the provision of means for reverse signaling a stretch of double track converging into a single track stretch, that permits normal movem nts on either one of the double tracks irrespective of the reverse control, when the switch at the junction of the two tracks is set for traffic from the single track stretch to the other of the two tracks. Other features of my invention will appear as the specification progresses.

I will describe certain forms of apparatus for railway signaling embodying my invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Figs. 1 and 1 when placed end to end with Fig. 1 at the left, are a diagrammatic view of one form of apparatus embodying my invention when applied to a stretch of double track railway converging into a stretch of single track. The arrangement is such as to permit routing of trailic in either direction over either of the tracks of the double track stretch. Figs. 2 and 2*, when placed end to end with Fig. 2 at the left, are a diagrammatic view of one form of apparatus embodying my inventionwhen applied to a stretch of single track.

In the following description reference is made to these drawings, in which like characters designate similar parts. At certain. places in the drawings, a circuit controlling contact is located at a point not adjacent to the governing relay in order to make the drawing easier to understand. In all such instances, the reference character which is applied to the governing relay is located just above the contact, and the contact is shown in the positioncorresponding to the normal condition of the relay. For example, in Fig. 1 the front contact designated by the reference char acter Si! is governed by'a relay RSR and this front contact is shown open because the relay RSR is normally deenergized.

Referring to Figs. 1 and 1 the reference character N designates the westbound track'and the reference character M designates the eastbound track of a stretch of double track railway extending between two locations X and Y. At location X, the two tracks M and N converge, througha switch SW, into a single track designated by the 1 reference character 0. The trafiic rails of these tracks are divided by the usual insulated rail joints into a plurality of track sections. Each track section is provided with the usual track 5 circuit consisting of a source of current such as a battery 3, and a track relay designated by the reference character TR plus a numeral corresponding to the section. These track relays are represented conventionally by dash lines coni nected to the track rails of the section at the end opposite the battery.

The stretch of double track is provided with a standard automatic signal system governing traffic in the normal direction on. each track, which system comprises signals 19 and I2 associated with the eastbound track M, and signals H and I 3 associated with the westbound track N. Located between the signals Hi and I2 and signals H and I3 there may be other automatic signals if the distance between these signals is great enough to warrant them. The automatic signal system may be any one of several well known forms. However, the control circuits for the automatic signals form no part of my invention and are not shown in the drawings for the sake of simplicity, but it will be understood that my invention requires no change in the standard control that may be used for such signals. The signals here shown are deemed sufiicient to illustrate a preferred manner in which apparatus of my invention may be associated with any standard signal system for a stretch of double track railway.

At location Y there are provided two signals L4 and L6, while at the location X there are pro vided two signals RA and RB. As will shortly appear, the signals RB and L4 are remotely 0011- trolled, in part at least, and are used for governing traffic in opposite directions over the track N, while the signals RA and L6 are in part at least remotely controlled and are employed for governing traffic in opposite directions over the track M, affording thereby what is commonly known to the art as reverse signaling for this stretch of double track. There are also provided signals LA and LB at location X for governing traffic over the switch SW in accordance with the usual practice at such layouts. The switch SW may be hand operated, or it may be remotely controlled through the medium of a switch operating mechanism indicated by the reference character SM. These wayside signals may be of the semaphore, color light, or position light type, and are here shown as upper quadrant three-position semaphore signals capable of displaying clear, caution and stop indications, except the two signals RB and L5 which are two-position signals capable of displaying clear and stop indications only.

A relay designated by the reference character RHS at the location X, and two relays designated by the reference characters L4HS and LEI-IS at the location Y, are manually controlled from a remote point, such as a despatchers office. The apparatus for controlling the relays RHS, LAI-IS and LBHS is not shown in the drawings, as it forms no part of my invention; it may be in accordance with any one of several well known centralized traffic control systems, or remote control systems, or it may consist of simple circuits governed by levers in a nearby tower. As a matter of fact, one such system may be used to control the relays at one location, and a dissimilar system used to control the relays at the other location. Sufiice it to say these relays are standard neutral relays governing circuit controlling contacts in the usual manner. It will be understood, however, that other devices could be used in place of the neutral relays here shown, as the means whereby an operator at a remote point may open and close circuit controlling contacts, without departing from the scope of my invention.

The remote controlled relay RHS at location X is normally deenergized and is adapted, as will shortly appear, to govern the operation of the signals RA and RB. In like manner, the remote controlled relays LQHS and LSHS atlocation Y are normally deenergized and govern the operation of the signals L4 and L6, respectively.

Associated withthe switch SW are two relays RK and NK energized by simple circuits that include a controller contact I4 governed by the position of the switch SW, the control of these relays being such that the relay NK is energized only when the switch is set in its normal position to direct traffic from the single track to the track M, and the relay RK is energized only when the switch is set in its reverse position to direct traffic from the single track 0 to the track N.

Associated with the track N is a traffic locking circuit for governing two trafiic directional relays BER and L4FR located at locations X and Y, respectively. Assuming the switch SW to be set in its reverse position to direct traffic from track 0 to track N, and the reverse switch repeater relay RK energized, one side of this trains looking circuit is from the positive terminal of a battery l at location X, through circuit controller contact it operated by the signal mechanism RB and closed only when that signal indicates stop, back contact H of the directional relay BFR, resistance l8, front contact 59 of an approach locking relay RIVER to be referred to later, back contact 2i! of the despatcher controlled relay RHS, front contact 2| of track relay ITR for the track section ST, front contact 22 of relay RK, line wire 24, front contact 23 of the track relay 3TH, the front contacts of all intervening track relays for all track sections between signals H and i3, front contact 25 of track relay 'ITR, front contact 26 of track relay 9TB, back contact 21 of despatcher controlled relay L 'lI-IS, back contact 28 of a directional stick relay USSR to be shortly described, resistance 29, back contact 30 of the directional relay L lFR, front contact 3| of an approach locking relay LGMR, and circult controller contact 32 operated by the signal L4 and closed only when that signal indicates stop to the positive terminal of a battery 33 located at location Y. The other side of this traf fie locking circuit normally extends from the negative terminal of battery l5 at location X through circuit controller contact 34 operated by signal RB, back contact 35 of directional relay BFR, frontcontact 36 of approach locking relay RMR, back contact 31' of despatcher controlled relay RHS, front contact 38 of track relay iTR, front contact 39 of relay RK, line wire 65, a front contact of each intervening track relay, back contact 4| of despatcher controlled relay L ll-IS, back contact 42 of directional stick relay LdSR. back contact 43 of directional relay LdFR, front contact 44 of approach locking relay L lMR, and controller contact 15 operated by signal L4 to the negative terminal of the battery 33. Thusnormally no current flows in this traific locking circuit just described, the voltage of the battery i5 opposing the voltage of the battery 33, it being understood that these two batteries are of substantially the same voltage. The approach locking relays RMR and L lMl-t are governed by traffic approaching the signals RB and L4, respectively, by any one of several methods commonly employed for such approach locking relays, and these circuits are omitted from the drawings for the sake of simplicity as they form no part of my invention.

With the despatcher controlled relay RHS energized, this traffic locking circuit is disconnected from the battery 15 at the back contacts 20 and 31 of relay RHS, and is then connected to the winding of the directional relay BFB at front contacts 48 and 41 of RHS. In this event, the relay BFR becomes energized by current supplied from the battery 33 at location Y if the in tervening track sections are all Lmoccupied and the apparatus at location Y is in its normal con. dition as shown in Fig. 1*. In like manner, the energizing of the despatcher controlled relay L4HS disconnects the traffic locking circuit from the battery 33 at its back contacts 2'? and 4| and connects the circuit to the winding of the directional relay L lFEt at front contacts 48 and 49, and relay L EFR then becomes energized by current supplied by battery l5 at location X in the event the intervening track sections are all unoccupied and the associated apparatus at location X is in its normal condition as shown in Fig. 1 It follows that the energizing of the proper despatcher controlled relay at either end of the protected territory of track N disconnects the tran'fic locking circuit from the current source at'that end and connects the circuit to the winding of a directional relay which is then controlled by current supplied to the traffic looking circuit by a source at the opposite end of the stretch of track.

At location Y, the directional stick relay LQSR is associated with the directional relay LtFR, and this stick relay is provided with a pick-up circuit that is closed as a westbound train enters the track section {5T wh n signal L lis at clear or caution. This pick-up circuit can be traced from the terminal B of a convenient source of current through back contact til of track relay fiTR, circuit controller contact all operated by the signal L4 and closed during the fifteen to thirty degree movement of its mechanism, and winding of relay L lSR. to the terminal C of the same source of current. The stick circuit for this relay L-lSR includes its own front contact 52 and the back contact 53 of the associated directional relay MFR. Hence, whenever this directional stick relay LclSR becomes energized, it is retained energized as long as its associated directional relay LGFR re mains deenergized.

The operation of the signal L4 is governed by a signal controlling or home relay L4H which is provided with an energizing circuit controlled by the directional relay LflFR, the directional stick relay L lSR and the despatcher controlled relay L4HS, as well as by the usual elements of the automatic signal system, which in this instance include the track relay for the first track section in advance of the signal and pole-changing contacts operated by the signal in advance. To be explicit, the energizing circuit for the relay L4H is from the terminal B of a convenient source of current not shown, pole-changing contact 56 for signal 13, line wire 51, front contact 58 of track relay 9TB, front contact 59 of directional relay L4FR, winding of relay L6H, front contact 69 of relay MFR, front contact 65 of despatcher controlled relay LGHS, front contact 62 of track relay 3TB, line wire 63, and pole-changing contact li t to the terminal C of the current source. Shunting around the front contacts 59 and 60 of the directional relay LtFR are two paths which include the front contacts 65 and 66, respectively of the directional stick relay LASR as will be readily understood by an inspection of Fig. 1*. With the pole-changing contacts 56 and 64 in the positions shown by the solid lines in Fig. l and which positions correspond to either the clear or the can-- tion position of signal l3, the relay Lei-l is energized with current of normal polarity, and when the contacts 56 and G l are shifted to the positions 'shown by dotted lines in Fig. l corresponding to the stop position of signal I 3, the relay L4H is energized with current of reverse polarity. When relay L4H is energized with current of normal polarity, its front neutral contacts 6? and TI are closed and its polarized contact 58 is held in the right-hand position, completing thereby an operating circuit that includes the wires 10 and 59 leading to the signal L4 for clearing that signal. When relay L4H is energized with current of reverse polarity, the closing of its front contacts 6'! and H completes the caution operating circuit which includes the wires 69 and 72 leading to signal L4, the polarized contact 68 being new shifted to its left-hand position. Hence, to clear the signal L4 for advancing traffic on track N in the normal westbound direction,

the despatcher will energize the relay LQHS to transfer the above-described tramc locking circuit from battery 33 to the winding of the directional relay LGFPA. If the associated apparatus at location X is in its normal condition and all intenvening track sections are unoccupied, the directional relay L lFR is picked up to establish the westbound direction of traffic. The signal controlling relay LdI-l is then in turn, energized to clear the signal Lt in accordance with the position of the signal 53 in advance and the trafic condition of the track section 9T. A westbound train moving past signal L 3 into the section 9T shunts the track relay iTR to open the traffic locking circuit at the front contact 25, so that the directional relay L lFR becomes deenergized and it will then remain in that condition as long as the westbound train occupies any one of the track sections. The directional stick relay L lSR, however, is picked up during the interval in which the circuit controlling contact 5! of signal L4 is closed as that signal drops to its stop position, and is then retained energized by its stick circuit as long as the directional relay L lFR. remains deenergized. Thus, as soon as the Westbound train vac-ates the section 9T, the signal controlling relay L l-H is reenergized due to its circuit being now closed at the front contacts 65 and 66 of the directional stick relay L lSR, and the signal L4 will be cleared automatically for following westbound trains. The despatcher can control the operation of signal L l by operating the relay L4HS. Should he deenergize the relay L4HS immediately after the first westbound train enters the section 9T, signal L l is held at stop but the directional stick relay USSR remains energized to maintain the westbound direction of traffic.

At the location X, switch SW, when in its normal position, causes the relay to be deenergized, closing at its back contacts 54 and 55: a connec tion for the traffic locking circuit around the contacts of track relay lTR, despatcher controlled relay RES and the approach locking relay RMR, as will be apparent by an inspection of Fig. 1 It follows that with switch SW set normal to move traffic from the single track 9 to the eastbound track M, the directional relay LQFR at location Y can be energized by the despatcher selecting relay LiHS if the track sections of track N are unoccupied, irrespective of the condition of the associated control relays at location X. Thus trains can be advanced westward on track N under the usual protection of the automatic signal system, irrespective of the reverse control, whenever switch SW is set to direct trafiic to track M. With the switch SW set in its reverse position to move trafiic from the single track to track N, the directional relay MFR can be selected only in the event the control relays at location X associated with the trafiic locking circuit of track N are in their normal conditions. That is, relay L'lFR can now be energized only in the event the despatcher controlled relay RHS and the opposing directional relay BFR are deenergized, the approach locking relay RMR is energized, and the opposing signal RB is at stop. In this latter case, the selecting of the directional relay LQFR and the subsequent clearing of the signal L to advance a train on track N in the normal westward direction is accompanied by the picking up of the directional stick relay L4SR in the manner already described as the first westbound train passes signal L4. While the despatcher is free to control the signal L4, the directional stick relay will retain the established westbound direction of traffic irrespective of any operation that may be made by the despatcher in controlling relay L4HS, until this stretch of track becomes entirely free of traflic. That is to say, once westbound traffic is established on track N, the despatcher is free to restore his relay 1.4118 to its normal condition immediately behind any westbound train to release the remote control system which includes that relay and he can then later reenergize the relay L4I-IS and clear the signal L l for a following westbound train although the first train still occupies the protected portion of track N. When the last westbound train has proceeded west out of the track section lT, the above described traffic locking circuit is restored and the directional relay LQFR is again picked up, opening the stick circuit for the di rectional stick relay LASR, and the latter relay is returned to its normal deenergized position. In the event the despatcher controlled relay L lI-IS has been deenergized during the time the track N was occupied by a westbound train, the connection to the winding of directional relay L SFR is completed at the back contacts 21 and 4! of relay L il-IS and the front contacts l3! and i552 of relay LASR. It follows that the directional relay L ll -R is picked up to restore the apparatus at location Y to its normal condition as soon as the stretch is free of westbound traffic irrespective of what operation may have taken place for the despatcher controlled relay L lI-IS.

Assuming the traffic locking circuit associated with track N to be normal as shown in the drawings, and that it is desired to establish eastbound traflic from the single track 0 at location X to location Y over the track N, the procedure is as follows. The despatcher selects the relay RHS at location X and so transfers the traffic locking circuit from the battery I5 to the directional relay BFR, which latter relay is then energized from battery 33 provided the associated control relays at location Y are in their normal conditions and all intervening track sections unoccupied. The switch SW will also be set in its reverse position, of course. The picking up of the directional relay BFR completes the circuit for the signal controlling relay RBH for the signal RB. This circuit for relay RBI-I is from terminal B of a current source, circuit controlling contact 13 operated by the opposing signal LB and closed when that signal indicates stop, front contact 14 of the reverse switch repeating relay RK as that relay is now picked up, front contact 15 of track relay ITR, front contact '16 of despatcher controlled relay RHS, front contact 17 of directional relay BFR, and winding of relay RBI-I to the terminal C of the same source of current. With relay RBI-I picked up to close its front contacts 78 and T9, the operating circuit for signal BB is completed and that signal cleared to permit a train to advance from track 0 over track N in the reverse direction.

To sum up thus far, when the switch SW is set in its normal position, the traffic locking circuit'for the track N is effective to permit trains to advance westward from location Y under the protection of the usual automatic signals provided the despatcher controlled relay L4HS is operated. The despatcher controlled relay at location X is at this time ineffective to control the trafiic locking circuit. When the switch SW is set in its reverse position to permit traffic to move from the single track 0 to the track N, the traffic locking circuit is effective to require cooperation between the despatcher controlled devices at the two locations X and Y in order to establish traffic in either direction. With normal westbound direction of traffic established by the energizing of the relay L4I-IS, the subsequent energizing of the directional relay LGFR causes the westbound signal L4 to be cleared. As the first westbound train enters the track section 9T, the directional relay L lFPt is deenergized and its associated directional stick relay L4SR picked up. With stick relay L4SR. up, westbound traffic is maintained as long as any westbound train occupies the protected stretch of track irrespective of the positions of the despatcher controlled relays, thus permitting any desired operation of these manually controlled devices without affecting the directional selection. As soon as the stretch of track becomes free of all traffic, the apparatus of the traflic locking circuit is automatically restored to its normal condition. Reverse direction of traffic is established on track N by the energizing of the despatcher controlled relay RES and the subsequent energizing of the directional relay BFR to clear the reverse signal RB. In this instance, no directional stick relay is provided for the directional relay BER and thus following moves in the reverse direction over track N cannot be made until the first train vacates the stretch. It is apparent, however, that a directional stick relay can be associated with the directional relay BFR in the same manner as the stick relay LQSR is associated with the directional relay L iFI-l should it seem desirable to do so.

A. traffic locking circuit which is similar to the one just described for the track N is provided for the track M. Associated with the traflic locking circuit for track M at location X are directional relay AFR, directional stick relay RSR, the despatcher controlled relay RHS and the approach locking relay BMR. At location Y there are provided, for the traffic locking circuit for track M, the despatcher controlled relay L'Sl-IS, a directional relay LEFR, and an approach locking relay LBMR.

At location X this trafiic locking circuit is connected to the positive terminal of the battery l5 through a circuit controller 8| operated by signal RA and closed only when that signal is at step, back contact 32 of directional relay AFR, back contact 83 of directional stick relay RSR, front contact 84 of approach locking relay RMR, back contact 85 of despatcher controlled relay RHS, front contact 86 of track relay lTR, front contact 81 of switch repeater relay NK, and line wire 88. This circuit can be traced from the negative terminal of-battery (5 through circuit controller 89 operated by signal RA and closed when it is at stop, back contact 90 of relay AFR,

back contact 9! of relay RSR, front contact 92 of relay RMR, back contact 93 of relay HHS, front contact 94 of track relay iTR, and front contact 95 of relay NK to the line wire 96. The line wires 88 and 95 extend through front contacts of all intervening track relays as will be apparent from Figs. l and 1 At location Y, this traffic locking circuit extends from the line wire 88 through back contact 91 of relay LGHS, back contact 98 of relay LGFR, front contact 99 of approach locking relay LBMR, circuit controller it]?! operated by signal L6 and closed only when that signal is at stop, and thence to the positive terminal of battery 33. The line wire 96 is connected-to the negative terminal of battery 33 over back contact IQI of relay LEI-IS, back contact I02 of relay LBFR, front contact I03 of relay LBMR, circuit controller w l operated by signal L6, and thence to the negative terminal of battery 33. Thus rornially no current flows in this traffic locking circuit, the voltage of batteries I5 and 33 opposing each other.

To establish traffic from the single track at location X to the location Y over track M, the despatcher will energize the relay RHS which disconnects battery I from the traffic looking circuit just described by opening back contacts 85 and 93, and connects the circuit to the winding of the directional relay AFR through front contacts Hi5 and I 06. Relay AFR is then picked up by current supplied by the battery at location Y if the intervening track sections of track M are unoccupied and the associated control relays at location Y are in their normal condition. Relay RHS being now energized and its front contacts Ill? and m3 closed, the picking up of the directional relay AFR to close its front contacts I89 and iii! completes the circuit for the signal controlling or home relay RAH and that relay is energized. This circuit for the signal controlling relay RAH is easily traced, and it seems sufiicient only to point out that with relays RHS and AFR energized in the manner just described, the relay RAH is governed by track relays iTR and E R and by the position of the pole-changing contacts operated by the signal is in the usual manner. That is, relay RAH is energized with current of normal polarity if signal I E! is at clear or caution, and with current of reverse polarity when signal I0 is at stop. Relay RAH governs the operating circuits for the signal RA as will he readily understood by an inspection of Fig. 1

It is to be here noted that although the despatcher controlled relay RI-IS governs the traf fic locking circuits for both track N and track M, the setting of the switch SW in its normal position to permit traific to move between track C- and track M deenergizes the relay RK, and the consequent closing of back contacts 54 and 55 of this relay renders the despatcher controlled relay RHS ineffective to control the traffic looking circuit for track N as described heretofore. The setting of the switch SW in its reverse position deenergizes the relay NK and closes at its back contacts H2 and II 3 connections from wires 88 and 95 to the back contacts 83 and 9! of relay RSR around the contacts 35 and 93 of the despatcher controlled relay RHS thus rendering the despatcher controlled relay RHS ineffective to govern the traific locking circuit for track M.

Assuming the eastbound signal RA to have been cleared in the manner above described, an

eastbound train upon entering the track section IT and shunting the track relay I TR closes the pick-up circuit for the directional stick relay RSR, which circuit includes the back contact I i I of track relay ITR as well as a circuit controller contact l M operated by the signal RA and closed during the fifteen to thirty degree position of the movement of its mechanism. Relay RSR is then retained energized by its stick circuit that in- With the directional stickrelay RSR picked up to close its front contacts 81land 1, which are included in the control circuit for the signal controlling relay RAH, relay RAH will be controlled by the despatcher controlled relay RHS, and by track sections IT and 2T in advance of signal RA, to clear the signal RA for following east bound trains. It is apparent that the despatcher controlled relay RI-IS can be operated while an eastbound train occupies the track Mwithout destroying the eastbound directional selection, be-- cause the directional stick relay RSR is retained energized as long asthe stretch is occupied. The vacating of the part of stretch of track M by eastbound traflic causes the directional relay AFR to be reenergized opening the stick circuit for relay RSR and restoring that relay to its normal condition. To establish reverse direction of traffic on track M, that is, Westbound traiiic; the despatcher will select relay LSHS to disconnect the battery (-23 from the traffic locking circuit for track M and connect thereto the directional re lay LBFR, which latter relay is then picked up by current supplied from the battery I5 at location X over the traffic locking circuit. With the switch SW set in its reverse position, relay LSFR is supplied with'current if the intervening track sections of track M are unoccupied, irrespective of the condition of the relays lTR, RHS and RMR at location X; When the switch SW is set normal, the relay L55 is supplied with current only if the associated control relays at location X are in normal condition and the track sections unoccupied. The energizing of relay LESFR closes at its front contacts I33 and I34,the operating circuit for the reverse signal Lfi. While no directional stick relay is shown associated with the directional relay LSFR such relay can be readily provided, and may be controlled in a manner similar to the stick relay RSR for the directionalrelay AFR.

Referring to the Figs. 2 and 2 the traffic'rails of a stretch ofsingle track are arranged into a plurality of successive track sections designated by the reference characters NET to WT, inclusive, by means of the usual insulated rail joints. The track sections IBT and HT include the switches SW S and. SW2, respectively, leading to passing sidings PS and PSI. It will be understood, however, that my invention is not confined to this particular arrangement of track and switches,

The wayside signals RAI, RBI, 6 and 8 govern eastbound traiiic, and signals LAl, LBI, I and 9 govern westbound trafiic over thisstretch of single track. The control circuits for the intermediate signals may be in accordance with any one of several standard schemes now in general use and are not shown inthe drawings as they form no part of my invention. The switches SWI and SW2 may be remotely controlled, or they may be hand operated. Associated with this stretch of single track is a traflic locking circuit similar to the trafiic locking circuits shown in Figs. 1 and 1 At the passing siding PS, there is provided a despatcher controlled relay RHS, a directional relay RFR, a directional stick relay RSR, and an approach locking relay RMR, together with signal controlling relays RBIH and RAIH. At siding Psi, a similar layout of apparatus is provided, consisting of despatcher controlled relay LI-IS, approach locking relay LMR, directional relay LFR, directional stick relay LSR, and two signal controllingrelays LAII-I and LBI H.

The trafiic locking circuit for the single track of Figs.-2 and 2 being similar to the traffic locking circuits described in detail in connection with Figs. 1" and l it is thought suificient to point out that normally no current flows in the circuit due to its being connected to the two batteries H8 and H9 located at opposite ends of the stretch of track, and that it includes a front contact of all intervening track relays.

To establish westbound tratfic, the despatcher will select relay LI-IS to disconnect the trafiic locking circuit from the battery H9 at its back contacts I20 and i2! and to connect the circuit to the Winding of the directional relay LFR at its front contacts E22 and I23. As directional relay LFR picks up, the control circuit for the signal controlling relays LAIH and LBIH is completed at the front contacts I24 and 125, and one of these relays is energized depending upon the position of the switch SW2. Relay LAIH is selected if the switch is in normal position and relay 2NK picked up to close its front contact I26, and relay LBIH is selected it the switch is in its reverse position and relay 2RK is energized to close its front contact I21. It follows that if signal 1 in advance is at clear or caution and the track sections MT, I5T, I6T and T are unoccupied, either signal LA! or LBI will be cleared in response to the energizing of the despatcher controlled relay LHS and the subsequent energizing of the directional relay LFR over the trafiic locking circuit. A westbound train advancing into the section i'iT will deenergize the directional relay LFR and will pick up the directional stick relay LSR by a pick-up circuit that includes the back contact I28 of track relay IITR, and circuit controller contact l35 of signal LB! or circuit controller contact 136 of signal LAI depending upon which signal has been cleared. The directional stick relay LSR is retained energized by its stick circuit that includes its own front contact H9 and the back contact I30 of directional relay LFR. Assuming that the signal LBI has been cleared and that a westbound train advances out of the siding PSI, it is apparent that the despatcher can operate the relay LHS as soon as this westbound train enters this stretch of track without affecting the directional selection due to the directional stick relay LSR being retained energized by its stick circuit. Hence, the despatcher is free to deenergize relay RHS, which will permit the switch SW2 to be operated to its normal position for traffic on the main track by the remote control system in the usual manner. The despatcher controlled relay LHS can then be reenergized, causing the signal LAI to be cleared as soon as the first westbound train has proceeded beyond the immediate track sections, and a second westbound train on the main track is then permitted to follow the first westbound train that proceeded out of the siding PSI. That is to say, the directional stick relay LSR permits the despatcher controlled relay LHS to be operated without destroying the direc tional selection, thereby allowing a change in the track set up for following trains. When the stretch of track becomes free of westbound traffic, the directional relay LFR is reenergized by the trailic locking circuit, the connection being completed at the front contacts I22 and 123 of the relay LHS if that relay remains energized, or

completed at the front contacts I39 and Hill of the stick relay LSR in the event relay LI-IS has directional stick relay RSR provide the same flexibility of movement for eastbound trafiic as is provided for westbound traffic by directional relay LFR and directional stick relay LSR.

Apparatus such as here disclosed permits a traffic locking circuit, adapted to establish both normal and reverse directions of traffic for a stretch of railway, to be controlled by either a lever of an interlocking machine, a remote control system, or a centralized trafiic control system, or a combination of such systems. Once the direction of traffic is established and a train has entered upon the protected territory, the directional selection is maintained until the territory is unoccupied, regardless of any change in the condition of the controlling system. Hence, my system permits changes in the track set up that provide flexibility of train movements Without sacrificing the protection afforded to traffic.

Although I have herein shown and described only certain forms of apparatus for railway sig naling embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a stretch of railway track arranged into track sections each of which is provided with a track circuit, a traflic locking circuit for the stretch controlled by the track circuit of each section of the stretch, a source of current at each end of the stretch normally connected to the trailio locking circuit, two directional relays one at each end of the stretch to govern trailic in opposite directions through the stretch, a despatcher controlled means at each end of the stretch adapted when energized to disconnect the traflic locking circuit from the current source at its end of the stretch and connect the directional relay located at its end of the stretch to said circuit for establishing the direction for traffic, and a directional stick relay for each directional relay, each having a pick-up circuit closed in response to a train entering the stretch and a stick circuit independent of the despatcher controlled means at the same end of the stretch but including a back contact of the associated directional relay to retain the selected direction for trafiic irrespective of the despatcher controlled means as long as said train occupies the stretch of railway.

2. In combination, a stretch of railway track arranged into track sections each of which is provided with a track circuit, a traffic locking circuit for the stretch controlled by the track circuit of each track section, a source of current at one end of the stretch normally connected to the traific locking circuit, a directional relay located at the opposite end of the stretch to govern traffic in a given direction through the stretch, manually controlled means adapted when energized to connect the trafiic locking circuit to said directional relay to establish traffic through the stretch in said given direction, a directional stick relay having a pick-up circuit closed in response to a train entering the stretch traveling in said given direction and a stick circuit independent of said manually controlled means but including a back contact of the directional relay to retain established the said given direction for trafiic irrespective of the manually controlled means as long as said train occupies the stretch of railway.

3. In combination, a stretch of railway track over which traiiic normally moves in a given direction arranged into track sections each of which is provided with a track circuit, a first entrance signal to govern traffic entering the stretch in the normal direction of trafiic, a second entrance signal located at the opposite end of the stretch to govern trafiic entering the stretch in the reverse direction of traiiic, a trafiic locking circuit for the stretch controlled in part by the track circuits of the stretch, a directional relay for each entrance signal adapted when energized to clear its signal, manually controlled means at each end of the stretch adapted when energized to connect the directional relay at its end of the stretch to the trafiic locking circuit for establishing the direction of traffic, and a directional stick relay associated with the directional relay governing traffic in the normal direction which has a pick-up circuit closed in response to a train entering the stretch traveling in the normal direction and a stick circuit including a back contact only of the associated directional relay and arranged to retain the normal direction of traific irrespective of he manually controlled means as long as said stretch remains occupied by a train traveling in the normal direction.

4. In combination, a stretch of railway track divided into sections each of which is provided with the usual track circuit including a track relay, a control circuit for said stretch including a front contact of each track relay, a directional relay, a despatcher controlled relay adapted when energized to connect the directional relay to said control circuit for energizing said relay provided the stretch is unoccupied, a signal controlling relay, means for energizing said signal controlling relay when said despatcher controlled relay and said directional relay are energized provided the first track section in said stretch is unoccupied, a signal operated by said signal controlling relay, a directional stick relay, means for energizing said stick relay when a train enters said first section provided said signal is clear, means for subsequently keeping said stick relay energized as ion as the train occupics the stretch irrespective of the condition of the despatcher controlled relay, and means operating when said stick relay is energized to remove the signal controlling relay from control by said directional relay.

5. In combination, a stretch of railway track ivided into sections each of which is provided with the usual track circuit including a track relay, a switch in the first section of the stretch to direct traffic to said stretch from either one of two routes, a control circuit for said stretch including a front contact of each track relay, a directional relay, a despatcher controlled relay adapted when energized to connect the directional relay to said control circuit for energizing said relay provided the stretch is unoccupied, a signal controlling relay for each of said two routes, means for energizing a signal controlling relay in accordance with the position of the switch when said despatcher controlled relay and said directional relay are energized provided the first track section in said stretch is unoccupied, a different signal operated by each signal controlling relay, a directional stick relay, means for energizing said stick relay when a train enters said first section from either route provided the corresponding signal is clear, means for subsequently keeping said stick relay energized as long as theitrain occupies the stretch, and means effective when said stick relay is energized to remove each signal controlling relay from the control by said directional relay and thereby permit operation of the despatcher controlled relay and the subsequent clearing of either signal for a following train while the first mentioned train occupies the stretch.

In combination, a stretch of railway track along whic traliic moves in both directions, said stretch being divided into sections each of which is provided with theusual track circuit including a track relay, a control circuit for said stretch including a front contact of each track relay, a directional relay at each end of the stretch, a despatcher controlled relay at each end of the stretch adapted when energized to connect the associated directional relay to said control circuit for energizing said relay provided the stretch is unoccupied, means for clearing a signal at each end of the stretch when the correspondingdespatcher controlled relay and directional relay are energized provided the first track section at its end of the stretch is unoccupied, a normally deenergized directional stick relay at each end of the stretch, means for energizing a directional stick relay when a train enters the first section at its end provided the corresponding signal is clear, means for keeping said directional stick relay subsequently energized as long as the train occupies the stretch irrespective of the condition of the despatcher controlled relay at the same end of the stretch, means effective when a stick relay is energized for clearing the corresponding signal irrespective of theassociated directional relay, and means for restoring an energized stick relay to its normal condition when the stretch becomes unoccupied.

7. In combination, a stretch of railway divided into sections each of which is provided with the usual track circuit including a track relay, a control circuit for saidstretch including a front contact of each track relay, a directional relay and a directional stick relay arranged to permit the clearing of a signal controlling traffic entering the stretch when either of said relays is energized, a manually controlled means adapted to connect the directional relay to said control circuit for energizing that relay if the stretch is unoccupied and thereby clear the signal, means for energizing the directional stick relay when a train enters the first section of the stretch provided the signal is clear, means for keeping said stick relay subsequently energized as long as the train occupies the stretch and then deenergizing said stick relay when the stretch becomes unoccupied irrespective of the condition of the manually controlled means.

8. In combination, a stretch of railway track divided into sections each of which is provided with the usual track circuit including a track relay, a control circuit for said stretch including a front contact of each track relay, a traffic relay, a remote controlled means adapted when selected to connect the traflic relay to said control circuit for energizing said relay provided the stretch is unoccupied, a signal for governing trafic through the stretch, means for clearing said signal in response to the selecting of the remote controlled means and the energizing of the trafiic relay, a normally deenergized stick relay, means for energizing the stick relay as a train enters the first track section provided the signal is clear, means for subsequently retaining the stick relay energized as long as the train occupies said stretch irrespective of operation of the remote controlled means, means effective when said stick relay is energized to remove the signal from the control by said trafiic relay, and means restoring the stick relay to its normal condition when the stretch becomes unoccupied.

9. In combination, a stretch of railway track along which traffic moves in both directions, said stretch being divided into sections each of which is provided with the usual track circuit including a track relay, a traffic locking circuit for the stretch including a front contact of each track relay, a directional relay and a directional stick relay at each end of the stretch arranged to establish traffic from their end of the stretch when either of said relays is energized, a manually controlled relay at each end of the stretch adapted when energized to connect the directional relay at the same end to the traffic locking circuit for energizing that relay provided the stretch is unoccupied and thereby establish the direction for traffic, means for energizing the associated directional stick relay as a train enters the first section of the stretch at that end after traffic has been thus established, and means for retaining said stick relay subsequently energized as long as a train occupies the stretch irrespective of the associated manually controlled relay for retaining the established direction for traffic until the stretch becomes unoccupied independent of any operation of the manually controlled relay.

10. In combination, an eastbound track and a westbound track extending between a first and a second location and which converge into a single track at a switch at the second location, a pair of signals for each of said eastbound and westbound tracks located one at each of said 10- cations to govern traffic in opposite directions, a directional relay for each signal effective when energized to permit the clearing of its signal, a traflic locking circuit for each o1": said eastbound and westbound tracks and extending between the two locations, a despatcher controlled means associated with each directional relay normally effective to connect the corresponding traihc looking circuit to a current source and effective when actuated to disconnect the current source from the said circuit and to connect thereto the associated directional relay for energizing that relay provided the opposing despatcher controlled means is normal, and means effective when the switch is set for the eastbound track to render the despatcher controlled means for the second location ineffective to control the trahic locking circuit for the westbound track and effective when the switch is set for the westbound track to render the despatcher controlled means at that location ineffective to control the traffic locking circuit for the eastbound track.

11. In combination, an eastbound track and a westbound track extending between a first and a second location and which converge into a single track at a switch at the second location, a traffic locking circuit for each track each circuit adapted to control traffic in opposite directions over its corresponding track between the second location and the first location, despatcher controlled means at each end of each of said trafiic locking circuits for controlling the traffic locking circuits and arranged that when a despatcher controlled means is selected the corresponding traiilc locking circuit is effective to establish traffic from that location provided the opposing despatcher controlled means is not selected, and means efective when the switch is set for the eastbound track to render the despatcher controlled means at said second location for controlling the traffic locking circuit for the westbound track ineffective to control that circuit, and means effective when the switch is set for the westbound track to render the despatcher controlled means at said second location for controlling the traffic locking circuit for the eastbound track ineiiective to control that circuit.

12. In combination, a stretch of railway track divided into sections each of which is provided with the usual track circuit including a track relay, a railway switch located at one end of the stretch and arranged to direct traffic over said stretch when set in one position and to direct tramo to another route when set in the opposite position, a normally deenergized directional relay at each end of the stretch to govern trafllc in opposite directions through the stretch, a trafic locking circuit including a front contact of each track relay, a manually controlled relay at each end of the stretch adapted when energized to connect the directional relay at the same end to the trafiic locking circuit for energizing that relay provided the stretch is unoccupied and the opposing directional relay is deenergized, and means eirective when the switch is set to direct trafilc to said other route to render the manually controlled relay at said one end of the stretch inefiective to govern the traffic locking circuit.

13. In combination, a stretch of railway track, a manually controllable device, a traffic circuit controlled by said manually controllable device and by trafiic conditions in said stretch and arranged to be energized only if said manually controllable device is in a given condition and if said stretch of track is unoccupied, a signal for governing traffic movements over said stretch, means controlled by said tra-lilc circuit for clearing said signal if said traillc circuit is energized, a stick relay, means controlled by said signal and by trafiic conditions in said stretch for energizing said stick relay if a train enters said stretch in response to an indication of said signal, means controlled by said traffic circuit for retaining said stick relay in the energized condition while said trafiic circuit is deenergized, and means controlled by said stick relay under given conditions for clearing said signal while said traihc circuit is deenergized.

14. In combination, a stretch of railway track, a manually controllable device, a traffic relay, a

circuit controlled by said manually controllable F device and by traliic conditions in said stretch for energizing said traffic relay only if said manually controllable device is in a given condition and if said stretch of track is unoccupied, a signal for governing traffic movements over said stretch, means controlled by said trafiic relay for clearing said signal if said trafiic relay is energized, a stick relay, means controlled by a train entering said stretch in response to an indication of said signal for energizing said stick relay, means controlled by said traffic relay for retaining said stick relay in the energized condition while said traffic relay is deenergized, means controlled by said stick relay under given conditions for clearing said signal while said traffic relay is deenergized, and means controlled by said stick relay for at times energizing said traffic relay if said manually controllable device is in a second given condition.

15. In combination, a stretch of railway track, a manually controllable device, a traffic relay, a circuit controlled by said manually controllable device and by trafllc conditions in said stretch for energizing said traflic relay only if said manually controllable device is in a given condition and if said stretch of track is unoccupied, a signal for governing traffic movements over said stretch, means controlled by said traffic relay for clearing said signal if said traific relay is energized, a stick relay, means controlled by a train entering said stretch in response to an indication of said signal for energizing said stick relay, means controlled by said traflic relay for retaining said stick relay in the energized condition While said trafilc relay is deenergized, and means controlled by said stick relay when energized for effecting the energization of the traffic relay to cause said stick relay to be released upon the movement of a train out of said stretch even though said manually controllable device is not in said given condition.

16. In combination, a stretch of railway track, a traffic relay, a traffic circuit controlled by traffic conditions in said stretch for energizing said trafiic relay, a signal for governing traffic movements into said stretch, means controlled by said trafiic relay for clearing said signal when said traffic relay is energized, a stick relay, a pick-up circuit controlled by a train entering said stretch in response to an indication of said signal for energizing said stick relay, a stick circuit controlled by a back contact of said traffic relay for retaining said stick relay in the energized condition, and a second tramc circuit controlled by said stick relay for at times energizing said traftrolled circuit for at times energizing said traflic' relay, a second energizing circuit for said trafiic relay controlled by traffic conditions in said stretch and including a front contact of said stick relay, and traflic governing means controlled by said trafiic relay for governing the movement of traific in said one direction into said given stretch of railway track.

18. In combination, a stretch of railway track, a trafiic relay, a stick relay, a pick-up circuit for said stick relay closed by a train moving in one direction into said stretch of railway track, a stick circuit for said stick relay including a back contact of said traific relay, a circuit controlled by traific conditions in said stretch for at times energizing said traffic relay, a second energizing circuit for said trafiic relay controlled by trafiic conditions in said stretch and including a front contact of said stick relay, and trailic governing means controlled by said traific relay for governing the movement of traffic in said one direction into said given stretch of railway track.

PAUL P. STOKER.

crzh'rrrrmrr hr chhhhcrmh.

Patent No. 2,609,719. .iuiy 3h, r935.

PAUL P. STGKER.

it is hereby ertiiied that error appears in the printed specificatimr of the ahhve numbered patent requiring correctin-h as foliews: Fags 8, first chlumh, line 54-55 slain: 19, for "ar that" read fer the second; and that the said Letters Patent should be read with this correction therein that the same may csrrform w the record of the case in the Patent Office.

Signed and sealed this 10th day 0? September, A. D. 5935.

Leslie Frazer (Seafi) Acting Cmhmissioner of Patents. 

